The Pentair FreshPoint F1S5-RC is the sediment replacement cartridge for FreshPoint under sink drinking water systems. It is built on 5 micron polypropylene media, which captures the sand, silt and rust particles that make tap water look and taste dull, and which will not impart taste, odor or color of its own. In a FreshPoint three-stage system this is the sediment stage, and it earns its keep twice over. It cleans up what you drink, and it takes the fine grit out of the water before it reaches the carbon block stages, which helps protect them and keeps flow rates where they should be. It is also the cartridge the certification depends on. The FreshPoint F3000-B2B and F3000-B2M are tested and certified by NSF International against NSF/ANSI Standards 42 and 53 and CSA B483.1, and certified by IAPMO R&T against NSF/ANSI 53 for the reduction of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). That certified performance is for the system running its complete Pentair cartridge set, this sediment cartridge together with the F2B2-RC2 set. Changing it is genuinely quick. Lift the locking bar, pull the old cartridge from the head, slide the new one in and drop the bar back into place. Integrated check valves mean the cold water line does not need to be shut off, and color-coded shapes confirm each cartridge is in the right position. Replace every 675 gallons or one year, or sooner if flow has diminished.